Selector



April 22, 1941. H. E. LINDSTRCM SELECTOR Filed Oct. 19, 1938 Patented Apr. 22, 1941 2,239,329

UNITED STATES PATENT QFFiCE SELECTOR Helge Edvard Lindstrom, Stockholm, Sweden, as-

signor to Telefona'tiebolaget L. M. Ericsson, Stockholm, Sweden, a company of Sweden Application October 19, 1938, Serial No. 235,855 In Sweden December 21, 1937 6 Claims. (Ci. 179-2752) The present invention relates to selectors of insulating pieces as supporting members for the type in which a multiple common to a pluthe wire bundles so as to ensure their correct rality of selecting mechanisms is provided, and positions with respect to the other parts of the in which said multiple consists of bare wires or selector. rods which extend substantially at right angles In the embodiment of the invention shown, to the direction of movement of the wipers durthe two main parts of the selector, or the muling the selecting operation. tiple field and the selecting mechanism, are ar- Known selectors of this type have the inranged at opposite sides of a plate A formed as convenience that the bank of contacts and the a supporting wall for the multiple field, said selecting mechanism have to be separately at- 10 supporting wall also constituting one of the walls tached to the selector frame by means of a pluof a compartment F for the selecting mechanism. rality of members, resulting in that the mutual As will be clear from the drawing the supporting positions of the selecting mechanism and the wall A is provided for said purpose with recesses bank of contacts becomes dependent on the or guide apertures U into which the insulating measure of accuracy with which the individual pieces J, which hold together the wire bundles supporting or auxiliary members can be manu- TR, may be inserted with their noses N, said factured. In such selectors a fine adjustment noses after insertion engaging with the lower of the position of the bank of contacts with reedges of the recesses in the manner of hooks. spect to the selecting mechanism is required in Supported on the abutting surface of the wall connection with the assembling of the selectors. 2e are also brackets K, which form supports for a The present invention has for its object to ledgeT extending between them, said ledge being eliminate said inconvenience and to simplify provided with recesses G corresponding to the the construction and manufacture of the selector. It consists substantially in the provision, bemult tween the selector mechanism and the bank of a rubber packing M or the like and with screw contacts, of a plate which is perpendicular to fastenings V arranged in slots R, at the ends the direction of movement of the wipers during of the ledge in such a manner as to enable the the selecting operation, said plate serving on the insulating pieces, and thus also the wire bundles, one hand as an abutment for supporting insulatto be held between the ledge T and the abutting ing members which hold together different surface of the plate A by fitting the projections bundles of wires or rods forming different groups P into the recesses G. As a result of the pressof contacts, and serving on the other hand as an ing of the insulating pieces from a suitable subabutment for projections or lips provided on the stance, for example Bakelite, shoulder surfaces base plate or the like for the selecting mech- S are also provided thereon, the distances of said anism. According to the invention the abutting 5 shoulder surfaces from the nearest multiple wire surface is formed as a supporting wall for the being for different wire bundles constant within bank of contac s, S d Supporting W811 a c very narrow limits. The elastic packing arranged stituting a wall in a compartment for housing on the ledge T provides a completely tight conng mechanisms. tact between the shoulder S and the abutting one or more selecti The invention will now be flescrlbed e 111 surface, said surface being preferably also prodetail having reference to the drawing attached duced through a pressing or pressure casting projections P on the msulating pieces J of the iple field. The ledge is also provided with to this specification and forming part thereof, operatio which drawing shows a general perspective view The insulating pieces are preferably arranged of a selector according to the invention. on the wire bundles with a pitch corresponding Furthest to the left on the drawing there is 4.5 to the vertical dimension of the space occupied shown the construction of the wire or rod by each selecting mechanism, brackets being also bundles forming the difierent groups of contacts provided on the supporting wall A at mutual verof the selector multiple. The wire bundle TR tical distances corresponding to the above menconsists of eleven pairs of wires held together by tioned pitch. In this manner a perfectly rigid means of insulating pieces J which can be atassembly of the supporting wall with its abutting tached to the wires by a pressing operation. The surface and the multiple field is obtained, an insulating pieces are provided at one end with assembly that can be effected according to faca projection P and at the other end with a nose tory methods witho t afteradjustment. Accord N, the provision of said nose rendering it possible, ing to the invention the supporting wall will then as will be clear from the following, to use the often consist of the walls of aplurality of selector on the different compartments cooperating in the manner of tongue and groove, whereas centering in the direction of movement of the selector wipers is obtained by means of shoulders, not shown, which cooperate with the selector frame.

As should be clear from the above the invention renders possible the ready assembling of the multiple field and the various selector compartments in their correct mutual positions, so that said compartments will form together the equivalent of a solid selector frame, such compartments having the advantage, however, in comparison with a solid frame, of being capable of manufacturing in standardized units, so that they can be readily adapted to an exchange of any desired size.

In the embodiment of the invention shown on the drawing each selector compartment is intended to house two selector mechanisms. compartment has the shape of a box from which the bottom, the cover and the front wall has been removed, the end walls of said box being adapted to be secured on a selector frame by means of shoulders and screws, one angle iron ST only of said frame being shown on the drawing. On the drawing the left hand end wall has been cut away, as will be clear from the cross-hatched left hand portion of the supporting wall A. The compartment is provided with ledges Q; and Q2 on which the base plates of the two selecting mechanisms are intended to rest. On the drawing only one selector has been shown in position in the compartment. The base plate, which is narrower than the compartment so that a clearance is formed at both of its side edges, is supported by the ledge Q2. Movement of the base plate in a direction upwards is prevented by a projection UR on each side wall and by a spring FJ which cooperates with a piece AN and presses the plate downwards and inwards. sequence projections or lips L1 and L2 pass through openings in the supporting wall, will bear on abutting surfaces D1 and D2 formed by the brackets K in the plane of the abutting surface of the plate A. A lip L3, which cooperates with edges D3 in an opening in the suphorizontal slot extending along the entire width of the multiple field allows insertion of the wipers BR! and BRZ into the multiple field.

Along its side edges the base plate of the selector is slotted through a great portion of its depth as shown at 0, so that the parts of the base plate resting on the ledge Q2 will be mechanically connected with the plate only at the inner and outer edge of the plate. Through said arrangement transmission of vibrations from the selecting mechanism to the compartment is prevented.

to a common abutting surface, rendering possible, as already mentioned, the assembling of the diiferent parts of the selector according to factory methods. The only adjustment necessary after assembly of the selector consists in fixing the positions of the selector wipers BRl,

BB2 on the shaft which by means of toothed wheels KH transmits movement to the wipers during the selecting operation.

I claim:

1. In a selector arrangement, a number of selecting mechanisms having movable wipers, a bare wire multiple common to a plurality of said selecting mechanisms. and extending substantially at right angle to the direction of movement of selector wipers during a selecting operation, a fixed Wall plate arranged between said selecting mechanisms and the wire multiple and extending perpendicularly to the direction of movement of the wipers during the selecting operamembers of insulating material ders on said supporting members for determining the position of said supporting member relative to the wall plate, and abutments on said wall plate for determining the position of the selecting mechanisms relativ to the wall plate.

2. In a selector arrangement, a number of selecting mechanisms mounted on a base plate, a bare wire multiple common to a plurality of said selecting mechanisms and extending substantially at right angle to the direction of movement of selector wipers during a selecting opera tion, a fixed supporting wall plate arranged between said selecting mechanisms and the wire multiple and extending perpendicularly to the direction of movement of the wipers during the and provided with attachment noses adapted to engage said apertures, shoulders on the supporting members for determining the positions of said plate, and means on the wall plate for determining the position of the base plate or the selecting mechanisms relative to the wall plate.

3. In a selector arrangement, a number of selecting mechanisms mounted on a base plate, a bare wire multiple common to a plurality of stantially at right angle to the direction of movement of selector wipers during a selecting operation, a fixed supporting wall plate arranged between said selecting mechanisms and the wire multiple and extending perpendicularly to the of movement of the wipers during the selectin operation, said wall plate having apermaterial each holding a bundle of multiple wires and provided with attachment noses adapted to engage said apertures, shoulders on the supportcarried by said wall plate, a ledge carried by said brackets, said ledge having recesses corresponding to projections on the supporting members of the wire bundles, and means for clamping the wire bundles in positions between the ledge and the wall plate.

4. A selector arrangement as claimed in claim 3, wherein portions of said brackets form abutinents for projections on the base plates of the selector mechanisms.

5. A selector arrangement. as claimed in claim 2 wherein the wall plate is provided with ledges for supporting the base plate of the selector mechanism.

6. In a selector arrangement, a number of movement of the wipers during the selecting selecting mechanisms having movable wipers, a operation, supporting members of insulating bare wire multiple common to a plurality of said material each holding a bundle of multiple Wires, selecting mechanisms and extending substanshoulders on said supporting members for detially at right angle to the direction of move- 5 termining the position of said supporting memment of selector wipers during a selecting operaber relative to the Wall plate, said wall plate tion, a fixed wall plate arranged between said having openings therein, and projections carried selecting mechanisms and the Wire multiple and by said base plate extending into said openings. extending perpendicularly to the direction of HELGE EDVARD LINDSTRC'BM. 

